Flotation frother



Patented Dec. 22, 1936 PATENT OFFICE FLOTATION FROTHER Ludwig J. Christmann, Jersey City, and David W.

Jayne, Jr., Elizabeth, N. J., assignors to American Cyanamid Company, New York, N. Y., a

corporation of Maine No Drawing. Avl l iication October '11, 1933,

' v Serial No. 693,150

13 Claims.

This invention relates to the flotation of ores for the recovery of the valuable minerals therein. More particularly, this invention relates to a new and highly efliclent means for producing froth in the flotation operation for the recovery of the minerals.

The practice of froth flotation of ores in order to obtainthe desired minerals therein in concentrated form has been well established. It is customary to grind the ore to a suitable degree of fineness, add water thereto in sufllcient amounts to produce a free flowing pulp and add flotation reagents thereto. Such reagents were generally of two types. The so-called promoters acted to 16 give selective adhesion of the valuable ore particles to the froth and the so-called frothers were intended to provide the bubbles which floated to I the surface of the pulp. These reagents were mixed with the pulp and the pulp subjected to 20 aeration, whereby the froth was formed'carrying the mineral particles to the surface where they were removed by various means from the remaining pulp.

The present invention is directed to a new frothing agent which has highly desirable properties. The frothing, agent should effectively. produce a large volume of froth, which is tough and which is capable of holding the ore particles. In accordance with the present invention we have found that certain aliphatic alcohols are capable of producing a large amount of froth in the pulp. These alcohols may be briefly described as having from '7 to 10 carbon atoms and have a boiling range from about 133 C. to 250 C. These alcohols are the primary, secondary and sometimes include the tertiary heptyl, octyl, nonyl and decyl alcohols. While we may use but a. single alcohol as a frother we prefer to use mixtures of two or more of such alcohols and we have found that among such mixtures those containing substantial proportions of the octyl and nonyl alcohols give the best results;-

We have further found that although these alcohols are excellent frothers they have a tendency to produce too much froth and this in turn results in the flotation of gangue as well as of the desired mineral. In other words, the over frothing tends to prevent the formation of a selective froth. We have found that this difiiculty may be overcome by adding to the frother a hydrocarbon, either of the aliphatic series or of the terpene series.

Specifically we have found that a substantially saturated. hydrocarbon fraction obtained from the treatment of petroleum oils, commonly called naphtha, and having a boiling point within the extreme range of 300 F. to 500 F. serves as an excellent means for controlling and stablizing the froth obtained from the above named alcohols. 6 We have also found that the hydrocarbonknown as di-pentene having a formula of CmHrc and obtained from pine oil is suitable for our purpose. The alcohols may be mixed with the hydrocarbons in varying proportions over-a relatively wide 10 I mixed with 40% of naphtha having a boiling range of 352 to 484 F.- A lead ore was finely ground and made into a pulp with water; To the pulp was added .030 pound of ethyl xanthate per ton of ore as the promoter and the pulp was di- 25 luted to about 22% solids. To this was added the above named mixture in an amount of .081 pound per ton of ore. The pulp was agitated in a flotation machine for six minutes and the froth was skimmed from the pulp. The recovery of 30 lead mineral was 96.28%.

In another test, a mixture of the above stated alcohols in the amounto'f 50% with 50% of dipentene was added to the pulp of lead ore in the amount of .090 poundper ton of ore in coniunc- 35 tion with .030 pound of, ethyl xanthate and a flotation operation conducted therewith. This resulted in a recovery of 96.16% of the mineral.

Under the same conditions, but using the old and-well-known pine oil as a frother the recovery of lead ore was only 90.78%. The loss in the tailings in the test with pine oil as a frother was more than doublethat with the above mentioned mixture of the present invention. In other words, by utilizing'the present invention the loss of ore in the tails was less than one-half of the loss when using the old frother.

While we have described our invention settin forth a few-specific embodiments thereof, it is 50 apparent that our invention is not limited to the details set forth. For instance the hydrocarbons mentioned for addition to the alcohols may be of various types and having different ranges of boiling points than those set forth 5 above. We mayutilize aromatic hydrocarbons such asbenzol, toluol, xylol, solvent naphtha and the like, all ofwhich are included in the term hydrocarbon as used herein. The frothers described herein are adapted for use on. a large variety of ores-which are amenable to flotation and the usefulness thereof is not at all limited to lead ores. Various sources of alcohols may be used, but we have found'that the alcohols of higher molecular weight within the stated range give somewhat better-results. From the above it is apparent that our invention is not limited, but is of broadscope in accordance with the claims appended hereto.

The hydrocarbons described in the present invention operate as stabilizers of the froth produced by the alcohols and prevent over-frothing. The hydrocarbons, of course, operate as stabilizers when present in an amount sumcient to reduce the over frothing of the alcohol. The amount of hydrocarbon necessary will vary somewhat with the composition of the alcohol mixture and with the particular flotation operation, but should always be present in amounts suflicient to exceed the stabilizing action. In the claims, the word "stabilizer is used in the, sense of an amount of material sumcient to result in stabilization of the frothing properties of the alcohol and will be used in no other sense.

What we claim is:

1. A method of froth flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of a saturated hydrocarbon in amounts suflicient to act as a stabilizer and an -aliphatic alcohol having from 'I to 10 carbon atoms, and subjecting the pulp to a froth flotation operation.

2. A method of froth flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother,

- the latter comprising a mixture of a naphtha fraction of petroleum in amounts sufiicient to act as a stabilizer and an aliphatic alcohol having from 7 to 10 carbon atoms, and subjecting the pulp to a froth flotationoperation.

3. A method of froth-flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of a naphtha fraction of petroleum in amounts suflicient to act as a stabilizer having an extreme boiling range within 300 F.-500 1?. and. an aliphatic alcohol having from 7 to 10 carbon atoms, and subjecting the pulp-to a froth flotation opera- -tion.

- act as a stabilizer and, an aliphatic alcohol having from 7 to 10 carbon atoms, the amount of said alcohol being greater than said hydrocarbon, and subjecting the pulp to a froth flotation notation.

5. A method of froth carbon atoms, and subjecting flotation of ores which adding thereto acollecting agent and a frother,

- the latter comprising a mixture of 10-50 parts of a saturated petroleum hydrocarbon and 90i-50 parts of an aliphatic alcohol having from '1 tq 10 the pulp to a froth flotation operation.

6. A method of froth flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture .of a saturated petroleum hydrocarbon in amounts suflicient to act as a stabilizer and an aliphatic alcohol having from 7 to 10 carbon atoms, the amount of frother being in excess of the collecting agent. and subjecting the pulp to a froth flotation operation.

7. A method of froth flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of a saturated petroleum hydrocarbon in amounts sufiicient to act as a stabilizer and at least two of the following alcohols: heptyl, octyl, nonyl, decyl, and subjecting the pulp to a froth flotation operation.

8. A method of froth flotation of ores which comprises providing a' pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of a saturated petroleum hydrocarbon in amounts suflicient to act as a stabilizer and at least two'of the following alcohols: heptyl, octyl, nonyt, decyl, the heptyl alcohol being in preponderance, and subjecting the pulp to a froth flotation operation.

9. A method of froth flotation of ores which comprises providing a pulpof ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of a saturated petroleum hydrocarbon in amounts suflicient to act as a stabilizerand at least two of the following alcohols: heptyl, octyl, nonyl, decyl, and including the normal and secondary alcohols, and

subjecting the pulp to a froth flotation operation. 1Q. A method 01" froth flotation of ores which comprises providing a pulp of ore with water,

act as a stabilizer and octyl and nonyl alcohols,

and subjecting the pulp to a froth flotation operation.

11. A method offroth flotation of ores which comprises providing a pulp of ore with water, adding thereto a collecting agent and a frother, the latter comprising a mixture of an aliphatic alcohol having from 7 to lltcarbon atoms and a hydrocarbon taken from the aliphatic and terpene seriesin amounts suflicient to act as a stabilizer, and subjecting the pulp to a froth flotation operation.

12. A method according to claim 1 in which the collecting agent is an organic substituted xanthate.

13. A method according to claim 1 in which the collecting agent is an alkoxy xanthate.

. LUDWIG J. CHRISTMANN.

DAVID W. JAYNE. Jr. 

